Ice accumulated on power lines during ice storms applies additional weight and pressure to the power lines and often causes the power lines to break or detach from the supporting posts, or even breaks the posts and causes power interruptions. It is impractical, time consuming and too expensive for power maintenance companies to constantly send workers to de-ice power lines in most areas. These resources are best spent fixing power lines brought down by storms and restoring power to residential and commercial structures as opposed to working preemptively to prevent other power lines from collapsing.
Several previous inventions have been developed that attempt to solve the problem of accumulated ice on power lines. For example, U.S. Pat. No. 2,870,311, Greenfield et al. disclose an electrical cable structure that contains an inner conductor and an outer conductor separated by an insulating material. When ice forms on these cables, a strong current is passed through the outer conductor to cause it to increase in heat, thereby melting the ice on the cable. U.S. Pat. No. 3,316,344, Kidd et al., and U.S. Pat. No. 3,316,345, Toms et al., disclose an electrical cable structure with an exterior composed of a magnetic material. When the outside temperature falls below a given range, this magnetic material allows more current to pass through, thereby causing the material to increase in heat and melt any ice on the cable. U.S. Pat. No. 3,835,269, Levin et al. disclose a device for de-icing a wire by generating electromagnetic pulses on the wire. The device is installed in close proximity to the wire and transported along the wire by a vehicle. U.S. Pat. No. 4,212,378, Hrovat discloses a device for de-icing power cables consisting of wheeled dollies mounted on a cable. These devices have scrapers for removing ice from the cable. U.S. Pat. No. 5,411,121, LaForte et al. disclose a device for de-icing cables which includes one pair of conductive wires connected to and helically wound along the cable. The conductive wires are connected to a pulsing device which generates an electromagnetic pulse within the wires which creates a repulsive force between the wires, which shakes the wires and shatters the ice that may be attached to the cable.
None of the above inventions disclose an effective and inexpensive apparatus that can be set to automatically de-ice power lines during ice storms with minimal power consumption and supervision.
The apparatus of the present invention provides many benefits to maintaining the integrity of power lines during ice storms.